Imaging nuclear medicine techniques such as WBC or gallium scanning may be used to identify areas of inflammation or infection. However, their use is infrequent due to their inherent technical and protocol challenges as well as poor spatial imaging resolution. Furthermore, these techniques rely on secondary sequelae of bacterial infection and consequent inflammation rather than binding the bacteria directly leading to ambiguity of correct diagnosis of true bacterial infection.
These limitations are particularly evident in cases where a patient has a bacterial infection, but no known methods are available to locate the area of bacterial infection in the patient without misdiagnosing areas of inflammation. For example, it is difficult distinguishing bacterial pneumonia from aspiration chemical pneumonitis. Nor are there any reliable techniques for distinguishing a bacterial infection from another infection that presents with similar symptoms. For example, it is difficult distinguishing bacterial pneumonia from viral infection. Nor are there any reliable techniques for distinguishing a bacterial infection from tumor. For example, it is difficult distinguishing bacterial infection from recurrent or metastatic cancer in the lungs. In all of these cases, excessive amounts of incorrect antibiotics may be administered to the patient contributing the problem of antibiotic resistant organisms. Additionally, inappropriate biopsies may occur in cases of diagnostic ambiguity, thereby resulting in high treatment costs, and the possibility of procedural complications. What is needed in the art is the development of better quantitative imaging tools to monitor bacteria in humans.
There is an unmet clinical need for improved methods to track engineered cells, including immune cells used for cell-based therapy and adoptive immunotherapy. Also needed are better quantitative imaging tools to monitor gene and cell therapies.